Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080303
Jizhen Li, Bing Lan
: During forward flight, the flow field of autorotating rotor was very complicated, which caused induced velocity of the disc plane difficult to be obtained. In order to analyze aerodynamic characteristics of the autorotating rotor, improved blade element theory, using the unlimited-bladed fixed wake method to establish a mathematical model, which could obtain velocity of the disc plane induced by fixed wake of autorotating rotor. According to the Biot-Savert Theorem, the expression of axial induced velocity of disc plane could be got by integerating. The circulation and induced velocity were all expanded into Fourier series by azimuth, and then axial induced velocity could be carried out by iteration. Combined the blade element theory, aerodynamic forces of the autorotating rotor was obtained, and then analyzed its aerodynamic characteristics.
{"title":"Improved Blade Element Theory and Autorotating Rotor Aerodynamic Characteristics Analysis","authors":"Jizhen Li, Bing Lan","doi":"10.23977/jemm.2023.080303","DOIUrl":"https://doi.org/10.23977/jemm.2023.080303","url":null,"abstract":": During forward flight, the flow field of autorotating rotor was very complicated, which caused induced velocity of the disc plane difficult to be obtained. In order to analyze aerodynamic characteristics of the autorotating rotor, improved blade element theory, using the unlimited-bladed fixed wake method to establish a mathematical model, which could obtain velocity of the disc plane induced by fixed wake of autorotating rotor. According to the Biot-Savert Theorem, the expression of axial induced velocity of disc plane could be got by integerating. The circulation and induced velocity were all expanded into Fourier series by azimuth, and then axial induced velocity could be carried out by iteration. Combined the blade element theory, aerodynamic forces of the autorotating rotor was obtained, and then analyzed its aerodynamic characteristics.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68788557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080105
{"title":"Research on transverse impact performance of pipe-in-pipe structure","authors":"","doi":"10.23977/jemm.2023.080105","DOIUrl":"https://doi.org/10.23977/jemm.2023.080105","url":null,"abstract":"","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68788800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080401
Biomimetic tessellation is the combination of biomimetic and tessellation principles. This paper conducted an in-depth study on those theory. First, the author introduced biomimetic pangolin scales and biomimetic aggregates fruit, and conducted a target study on their animal and plant morphology by using the biomimetic tessellation principle. Second, according to the advantages obtained, the author chooses a suitable building case and makes innovate application of two biomimetic tessellation principle to test its rationality. The conclusion shows that the two biomimetic tessellation principles can greatly improve the building in the aspects of shading, comfort, flexibility, stability, economy, etc., which provides ideas and directions for future research.
{"title":"Research and Innovative Application of Biomimetic Tessellation Principles","authors":"","doi":"10.23977/jemm.2023.080401","DOIUrl":"https://doi.org/10.23977/jemm.2023.080401","url":null,"abstract":"Biomimetic tessellation is the combination of biomimetic and tessellation principles. This paper conducted an in-depth study on those theory. First, the author introduced biomimetic pangolin scales and biomimetic aggregates fruit, and conducted a target study on their animal and plant morphology by using the biomimetic tessellation principle. Second, according to the advantages obtained, the author chooses a suitable building case and makes innovate application of two biomimetic tessellation principle to test its rationality. The conclusion shows that the two biomimetic tessellation principles can greatly improve the building in the aspects of shading, comfort, flexibility, stability, economy, etc., which provides ideas and directions for future research.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135596066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080302
Hengqiang Liao
: Process processing is a complex and very important step in the machining process of CNC lathes, closely related to the compilation of machining programs, the quality and effectiveness of part machining. Process processing includes analyzing part drawings, calculating coordinate point dimensions, determining the cutting tools of CNC lathes, requirements for tool installation, formulating machining plans, and determining cutting quantities. To master the process processing of CNC lathe machining, it is not only necessary to master the process regulations and cutting knowledge of ordinary lathe machining, but also to have a solid basic knowledge of machining technology. It is necessary to have a comprehensive understanding of various aspects of formulating process plans in CNC lathe machining.
{"title":"The Processing Method of CNC Lathe Processing Technology for Complex Parts","authors":"Hengqiang Liao","doi":"10.23977/jemm.2023.080302","DOIUrl":"https://doi.org/10.23977/jemm.2023.080302","url":null,"abstract":": Process processing is a complex and very important step in the machining process of CNC lathes, closely related to the compilation of machining programs, the quality and effectiveness of part machining. Process processing includes analyzing part drawings, calculating coordinate point dimensions, determining the cutting tools of CNC lathes, requirements for tool installation, formulating machining plans, and determining cutting quantities. To master the process processing of CNC lathe machining, it is not only necessary to master the process regulations and cutting knowledge of ordinary lathe machining, but also to have a solid basic knowledge of machining technology. It is necessary to have a comprehensive understanding of various aspects of formulating process plans in CNC lathe machining.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68788510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080206
Guihua Huang, Tingting Zhang, Changxiang Chen
: In the process of PCB board production, it is necessary to accurately measure the contour dimensions of the PCB board and the dimensions of various types of wires, holes, or slots on the PCB board to avoid a large number of defective products flowing into the subsequent production process. In existing technology, the measurement of the dimensions of wires, holes, or slots on the PCB board mostly relies on manual work, which has the problems of low measurement efficiency and high measurement error rate, Unable to meet the efficient and high-quality production needs of PCB boards. This article proposes a method and device for effectively utilizing OpenCv to detect PCB board size. This device is based on an optical image measurement system, combined with the template matching method in OpenCv, and can automatically complete forming inspection and size measurement by scanning multiple PCB boards by one time.This device can complete measurement evaluation, report generation, and SPC data analysis for multiple PCB boards, achieving high automation and significantly improving measurement accuracy system.
{"title":"Method and Device for Effectively Utilizing OpenCV to Detect PCB Board Size","authors":"Guihua Huang, Tingting Zhang, Changxiang Chen","doi":"10.23977/jemm.2023.080206","DOIUrl":"https://doi.org/10.23977/jemm.2023.080206","url":null,"abstract":": In the process of PCB board production, it is necessary to accurately measure the contour dimensions of the PCB board and the dimensions of various types of wires, holes, or slots on the PCB board to avoid a large number of defective products flowing into the subsequent production process. In existing technology, the measurement of the dimensions of wires, holes, or slots on the PCB board mostly relies on manual work, which has the problems of low measurement efficiency and high measurement error rate, Unable to meet the efficient and high-quality production needs of PCB boards. This article proposes a method and device for effectively utilizing OpenCv to detect PCB board size. This device is based on an optical image measurement system, combined with the template matching method in OpenCv, and can automatically complete forming inspection and size measurement by scanning multiple PCB boards by one time.This device can complete measurement evaluation, report generation, and SPC data analysis for multiple PCB boards, achieving high automation and significantly improving measurement accuracy system.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68788893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080307
The multi-actuator load-sensitive (LS) system has gained widespread usage in engineering machinery applications due to its energy efficiency, exceptional composite action performance, and precise tuning capabilities. However, when the demand for load flow exceeds the supply of hydraulic pumps, flow saturation conditions may arise in hydraulic pumps, thereby impacting the coordination of multi-actuator actions and diminishing the load sensitivity characteristics of the system. To address this issue, scholars have proposed anti-flow saturation technology. Currently effective solutions include reducing the set pressure of pressure compensator valve springs and decreasing the opening degree of each main valve. Anti-flow saturation technologies for multi-actuator load-sensitive systems can be classified into three types based on the location of pressure compensators in different circuits: pre-valve; post-valve and outlet pressure compensation anti-saturation, as well as a novel type known as independent metering (IM) technology. This article provides an overview of significant accomplishments in these three types of anti-saturation technologies before introducing IM technology and discussing research focal points for various types of load-sensitive systems as well as how anti-saturation technologies impact their energy efficiency. Finally, future directions for development in flow saturation resistant technologies within muti-actuators load sensing systems are explored.
{"title":"A Review of Flow Saturation Resistant Techniques in Multi-actuators Load Sensing Hydraulic System","authors":"","doi":"10.23977/jemm.2023.080307","DOIUrl":"https://doi.org/10.23977/jemm.2023.080307","url":null,"abstract":"The multi-actuator load-sensitive (LS) system has gained widespread usage in engineering machinery applications due to its energy efficiency, exceptional composite action performance, and precise tuning capabilities. However, when the demand for load flow exceeds the supply of hydraulic pumps, flow saturation conditions may arise in hydraulic pumps, thereby impacting the coordination of multi-actuator actions and diminishing the load sensitivity characteristics of the system. To address this issue, scholars have proposed anti-flow saturation technology. Currently effective solutions include reducing the set pressure of pressure compensator valve springs and decreasing the opening degree of each main valve. Anti-flow saturation technologies for multi-actuator load-sensitive systems can be classified into three types based on the location of pressure compensators in different circuits: pre-valve; post-valve and outlet pressure compensation anti-saturation, as well as a novel type known as independent metering (IM) technology. This article provides an overview of significant accomplishments in these three types of anti-saturation technologies before introducing IM technology and discussing research focal points for various types of load-sensitive systems as well as how anti-saturation technologies impact their energy efficiency. Finally, future directions for development in flow saturation resistant technologies within muti-actuators load sensing systems are explored.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135502342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080203
{"title":"Design and Application of Fuel Supply Device and Fuel Supply Advance Angle Adjustment System","authors":"","doi":"10.23977/jemm.2023.080203","DOIUrl":"https://doi.org/10.23977/jemm.2023.080203","url":null,"abstract":"","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68788854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080403
Wave-shaped web plate steel replaces the traditional flat web plate in order to achieve greater planar stiffness and higher shear buckling capacity with a thinner web plate thickness. Additionally, the local compressive load-bearing capacity and fatigue resistance are also improved, resulting in higher load-carrying capacity and economic advantages for this type of steel. This translation summarizes the research conducted by domestic and international scholars on wave-shaped web plate steel, focusing on its stability performance, shear buckling, fatigue resistance, and stress concentration. Finally, it concludes by discussing the factors influencing these four performance aspects and proposes improvement methods.
{"title":"Review of Research on Corrugated Web Steel Beams","authors":"","doi":"10.23977/jemm.2023.080403","DOIUrl":"https://doi.org/10.23977/jemm.2023.080403","url":null,"abstract":"Wave-shaped web plate steel replaces the traditional flat web plate in order to achieve greater planar stiffness and higher shear buckling capacity with a thinner web plate thickness. Additionally, the local compressive load-bearing capacity and fatigue resistance are also improved, resulting in higher load-carrying capacity and economic advantages for this type of steel. This translation summarizes the research conducted by domestic and international scholars on wave-shaped web plate steel, focusing on its stability performance, shear buckling, fatigue resistance, and stress concentration. Finally, it concludes by discussing the factors influencing these four performance aspects and proposes improvement methods.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135650884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080404
With the incidence of cervical cancer in women rising year by year, its impact on the physical and mental health of patients as well as their families is becoming more and more significant. At present, hospitals often use intracavitary radiation therapy, and intracavitary therapy transfer bed as a gynecological oncology intracavitary radiation medical auxiliary device plays an extremely important role. Therefore, for the design of intracavitary therapy transfer beds, the validation of man-machine adaptability can well help to optimize its structure. The paper firstly imports the three-dimensional model of intracavitary therapy transfer bed established in UG software into the ergonomics analysis software Jack; secondly, in the analysis environment, it establishes the human body model that conforms to the body dimensions of patients with cervical cancer as well as the human body model of healthcare workers; then, on this basis, it establishes the simulation model for the patient's posture of using the intracavitary therapy transfer bed as well as for different movements of the healthcare workers in the course of the treatment; finally, it analyzes the stresses of the patient's lower limbs, as well as the waist, back, and upper limbs of the healthcare workers through the simulation and analyzes the comfort of the patients and the healthcare personnel with respect to the different movements of the treatment task. The analysis of the simulation results can verify the rationality of the design of the intracavitary therapy transfer bed and the use of comfort, and at the same time, combined with the results of the analysis of the healthcare worker's working posture, to provide an analysis method for the structural optimization of the intracavitary therapy transfer bed.
{"title":"Human factor ergonomic analysis of cervical cancer intracavitary therapy transport process based on Jack virtual simulation technology","authors":"","doi":"10.23977/jemm.2023.080404","DOIUrl":"https://doi.org/10.23977/jemm.2023.080404","url":null,"abstract":"With the incidence of cervical cancer in women rising year by year, its impact on the physical and mental health of patients as well as their families is becoming more and more significant. At present, hospitals often use intracavitary radiation therapy, and intracavitary therapy transfer bed as a gynecological oncology intracavitary radiation medical auxiliary device plays an extremely important role. Therefore, for the design of intracavitary therapy transfer beds, the validation of man-machine adaptability can well help to optimize its structure. The paper firstly imports the three-dimensional model of intracavitary therapy transfer bed established in UG software into the ergonomics analysis software Jack; secondly, in the analysis environment, it establishes the human body model that conforms to the body dimensions of patients with cervical cancer as well as the human body model of healthcare workers; then, on this basis, it establishes the simulation model for the patient's posture of using the intracavitary therapy transfer bed as well as for different movements of the healthcare workers in the course of the treatment; finally, it analyzes the stresses of the patient's lower limbs, as well as the waist, back, and upper limbs of the healthcare workers through the simulation and analyzes the comfort of the patients and the healthcare personnel with respect to the different movements of the treatment task. The analysis of the simulation results can verify the rationality of the design of the intracavitary therapy transfer bed and the use of comfort, and at the same time, combined with the results of the analysis of the healthcare worker's working posture, to provide an analysis method for the structural optimization of the intracavitary therapy transfer bed.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136207035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.23977/jemm.2023.080210
Zhao Long, Ma Jianhai, Li Shuang
: This article focuses on the problems of low operating efficiency, multiple soil working components, poor trafficability, and poor adaptability of current domestic no tillage seeders. Combining with the agricultural mode of planting wheat and corn in the double cropping area of the year, the structure of the seeder is optimized, and an intelligent wheat and corn universal no tillage seeder with one machine, dual use, deep loosening, and layered fertilization is studied and designed.
{"title":"Research on a Universal No Tillage Seeder for Wheat and Corn","authors":"Zhao Long, Ma Jianhai, Li Shuang","doi":"10.23977/jemm.2023.080210","DOIUrl":"https://doi.org/10.23977/jemm.2023.080210","url":null,"abstract":": This article focuses on the problems of low operating efficiency, multiple soil working components, poor trafficability, and poor adaptability of current domestic no tillage seeders. Combining with the agricultural mode of planting wheat and corn in the double cropping area of the year, the structure of the seeder is optimized, and an intelligent wheat and corn universal no tillage seeder with one machine, dual use, deep loosening, and layered fertilization is studied and designed.","PeriodicalId":32485,"journal":{"name":"Journal of Engineering Mechanics and Machinery","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68788482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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